We all know that all cars come with a plaque with the so called correct tyre pressures on it, but I have always found the need to increase this figure a fair bit for optimum performance, I don't mind sacrificing a little comfort for a better steering car.
I have always been fussy with my tyre pressures, but I have been having so much fun with the rest of my 9 that I had forgotten about re-adjusting tyre pressures until the other day when I was towing my boat I noticed the back tyres looked a little flat, then I realised that it was in getting the 1000k check over from the dealer the week before and they must have adjusted the pressures. I then put the gauge on them and found all 4 wheels had exactly 32psi in them.
Mine has the 20" wheels, but would be interested to hear from all, what pressures you run in your CX9, and that can be for both 18 & 20" wheels.
Maybe then I can take an average of all and come up with the best tyre pressure.